#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
int main()
{
	int m = 0, n = 0, num = 0;
	for (n = 1;n <= 100;n++)
	{
		m = n;
		if (m % 10 == 9)
			num++;
		if (m / 10 == 9)
			num++;
	}
	printf("%d\n", num);
	return 0;
}